Azo-dyestuffs



United States Patent 3,174,961 AZO-DYESTUFFS Karl Ronco, Muttenz,Switzerland, assignor to Ciba Limited, Basel, Switzerland, a company ofSwitzerland No Drawing. Filed Dec. 28, 1961, Ser. No. 162,938 Claimspriority, applicaiison/givitzerland, Jan. 6, 1961,

6 Claims. (Cl. 260203) This invention provides azo-dyestuffs which arefree from groups imparting solubility in water, especially sulfonicacid, carboxylic acid or carboxylic acid amide groups, and correspond tothe general formula in which R and R represent benzene or naphthaleneradicals, R represents an aryl radical, and R represents a naphthaleneradical in which the azo, hydroxyl and carboxylic acid amide groups arein the 1-, 2- and 3-pos1- tions, respectively. The invention alsoprovides a process for the manufacture of the above azo-dyestufis,wherein 1 molecular proportion of a dicarboxylic acid halide which isfree from groups imparting solubility in water and has the formula (2)N=NR1COHal CONHR -COHa1 in which R R and R have the meanings givenabove, and especially one of the formula N=N A in which Z represents analkoxy, alkyl or a substituted phenoxy group or a halogen atom, and inwhich the benzene radicals A and B may be further substituted and thecarboxylic acid chloride group in ring A is in metaor para-position tothe azo group, is condensed with 2 molecular proportions of an aromaticmonoamine which is free from groups imparting solubility in water.

The azo-dicarboxylic acids, from which the acid halides of Formula 2 areprepared, are obtained by coupling a diazo-compound of an aminobenzoicacid or aminonaphthoic acid with a compound of theformula I t C ONH-R3-CO OH in which R and R have the meanings given above.

Examples of such aminobenzoic acids are paraor especiallymeta-aminobenzoic acids, preferably those containing a substituent, forexample, a halogen atom or an' alkoxy group, in ortho-position to theamino group. Examples are: meta-aminobenzoic acid, 4-chloro-3-amin0-benzoic acid, 4-methoxy-3-aminobenzoic acid, S-amino-2:4-dichlorobenzoic acid, 4 (para-chloro)-phenoxy-3- aminobenzoic acid,4-amino-3-nitrobenzoic acid and 4- methyl-3-aminobenzoic acid. Thecoupling components of Formula 4 can be obtained, for example, bycondensing a 2:3-hydroxynaphthoic acid halide with an aminobenzoic acid.The 2:3-hydroxynaphthoic acid halide may be substituted in the6-position of the benzene ring not amino-2-methoXy-5-nitr0b enzene.

3,174,961 Patented Mar. 23, 1965 "Ti ce containing the carboxylic acidgroup by, for example, a halogen atom, especially a bromine atom, or byan alkoxy or alkyl group. However, it is preferable to use2:3-hydroxynaphthoic acid chloride itself on account of its easyavailability.

The aminobenzoic acid or aminonaphthoic acid of the formula H N-R COOHto be condensed therewith, advantageously contains the amino group inmetaor para-position to the carboxylic group, and may contain furthersubstituents, such as halogen atoms or alkoxy or nitro groups. Exmplesare: paraor 'meta-aminobenzoic acid, 3- amino 4:6 dichlorobenzoic acid,3 amino 4- methoxybenzoic acid and 4-amino-3-nitrobenzoic acid.

The azo-dicarboxylic acids so obtained are treated with an agent whichis capable of converting carboxylic acids into their halides, forexample, their chlorides or'bromides, especially a phosphorus halide,such as phosphorus pentabromide or phosphorus trichloride orpentachloride, a phosphorus oxyhalide or preferably thionyl chloride.

The treatment with such acid-halogenating agents is advantageouslycarried out in an inert organic solvent, such as dimethyl-formamide, achlorobenzene, for ex ample, monoor di-chlorobenzene, or toluene, xyleneor nitrobenzene, the five last mentioned solvents being used, ifdesired, together with dimethyl-formamide.

In preparing the carboxylic acid halides it is generally of advantagefirst to dry the azo-compounds, since they have been prepared in anaqueous medium, or to free them from water azeotropically by boilingthem in an organic solvent. If desired, this azeotropic drying may becarried out immediately before treatment with the acidhalogenatingagent.

In the process of the invention, the dicarboxylic acid halides soobtained are condensed with aromatic monoarnines in the molar ratio 1:2.Examples of aromatic monoamines are aminonaphthalenes, such as 1- or 2-naphthylamine, 1 amino-5:S-dichloronaphthalene, 2- amino-G-methoxyor2-amino-6-bromonaphthalene, and especially amino-benzenes, for example,-1-arnino-2:5-dichlorobenzene, 1-amino-2:4:5-trichlorobenzene or 1- Ofspecial interest are monobenzoylated diaminobenzenes especially thosehaving the formula in which X and Y represent hydrogen atoms or alkyl oralkoxy groups containing 1 or 2 carbon atoms, or especially halogenatoms, for example, bromine or preferably chlorine, and in which thebenzene nucleus C may be further substituted. Examples are:1-amino-4-benzoylaminobenzene, 1 amino-4-(para-chlorobenzoylamino)-benzene, 1 amino-4-(para-methoxybenzoyl)-aminobenzene,l-amino-2-chloro-4-benzoylaminobenzene, l-amino- 2:5dichloro-4-benzoylaminobenzene,l-amino-Z-methoxy-S-chloro-4-benzoylaminobenzene, and 1-amino-2z5-dimethyl-4-benzoylaminobenzene. A mixture of different acid chlorideswithin the above definition may be condensed with the same monoamine,whereby the tint of the dyestuff can be modified.

The condensation of the aforesaid carboxylic acid halides with theamines is advantageously carried out in an anhydrous medium. In thiscase the condensation takes place surprisingly easily, even attemperatures within the boiling range of normal organic solvents, suchas toluene, monochlorobenzene, dichlorobenzene, trichlorobenzene,nitrobenzene or the like. It is of advantage to use an agent capable ofbinding acid, such as anhydrous sodium acetate or pyridine, in order toaccelerate the reaction. Some of the dyestuffs so obtained arecrystalline and others are amorphous, and they are generally obtained ina very good yield and in a pure state. It is of advantage first toisolate the acid chlorides obtained from the carboxylic acids. In somecases, however, the isolation of the acid chlorides may be dispersedwith without harm, and condensation carried out immediately followingtheformation of the carboxylic acid chlorides.

The new dyestuffs of the invention are valuable new pigments which, byvirtue of their insolubility in organic solvents and their resistance toheat, are very suitable for coloring plastics, principally red tints.They possess excellentfastn'ess to light and migration. Apart from usingthem for coloring plastics, the pigments of the invention can also beused for pigment printing that is to say, for printing processes inwhich a pigment is fixed on a substratum, particularly a textile fabricor another sheetlike substratum, such as paper (e.g., wallpaper) or afabric of glass-fibers, with a suitable adhesive, such as casein, athermo-setting resin, particularly a ureaor melamine-formaldehydecondensation product, or solutions or emulsions of polyvinyl chloride orpolyvinyl acetate, or other emulsions (e.g., oil-in-water orwater-in-oil emulsions). The pigments can also be used in a finelydivided form for the spin-dyeing of rayon or viscose or cellulose ethersor esters or polyainides or polyurethanes, and also for the manufactureof colored lacquers or lacquer-formers, solutions or products ofacetyl-cellulose, nitrocellulose, natural or synthetic resins, such aspolymerization or condensation resins, for example, aminoplasts,phenoplasts, polystyrene, polyethylene, polypropylene, polyacrylates,rubber, casein, silicone or silicone resins. They can also be used inthe manufacture of colored pencils, cosmetic preparations or laminatedsheet material.

Preparations which contain such pigments in a finely divided form can beproduced in known manner by intense mechanical treatment, for example,on a roller mill or in a suitable kneading apparatus. The dispersingmedium in which they are subjected to the intensive mechanicaltreatment, is chosen to suit the preparation to be made, for example,sulfite cellulose waste liquor or a salt of dinaphthyl-methanedisulfonic acid is used for the manufacture of preparations that are tobe dispersible in water, and acetyl cellulose mixed with a littlesolvent is used for the production of compositions for spinningcellulose acetate rayon.

Owing to the especially favorable physical form in which the pigments ofthis invention are obtained, and by virtue of their chemical inertnessand good heat resistance, they can be easily dispersed in the usualmanner in the aforesaid masses and preparations, and this isadvantageously carried out at a stage before the said masses orpreparations have reached their final form. The opera- Example 1 49parts of the monoazo-dyestutf, obtained by coupling diazotized4-chloro-3-aminobenzoic acid with Z-hydroxy- 3-naphthoic acid (3-carboxy)-phenylamide, are heated at 120130 C. for 1 hour with 1000- partsof orthodichlorobenzene, 25 parts of thionyl chloride and 5 parts ofdimethyl formamide.

After cooling the reaction mixture, the dicarboxylic acid chloride,which has precipitated in the form of thin red needles, is filtered off,washed with benzene and dried in vacuo at 50 C.

26.5 parts of the dicarboxylic acid chloride are added to 1000 parts ofortho-diohlorobenzene at C., while stirring. 30 parts of2:5-dich1oro-4-benzoylamino-1- aminobenzone in 500 parts ofortho-dichlorobenzene are poured in, and the whole is heated at 140-145C. for 16 hours. The precipitated crystalline pigment is filtered at C.,Washed with hot ortho-dichlorobenzene, hot benzene and methanol, anddried at 7080 C. in vacuo. A soft grained red powder is obtained whichcolors polyvinyl chloride foils a bright scarlet tint which is fast tolight and migration.

The product thus obtained has the formula do-NH-ONHOO-O In a manneranalogous to that described in Example 1 the azo-dyestuff dicarboxylicacids, obtained from the diazo-components, H N-R COOH, in column I ofthe following table and the coupling components,

R2 C ONHR3C 0 OH in column II are reacted in the form of theirdicarboxylic acid cfhlorides with 2 molecular proportions of thearcmatic amines in column OIII. Column IV gives the colors tronsrequired for giving the products their final form, 55 produced with thepigments in polyvinyl chloride fOllS.

No. I II III IV 1 i-chloro-3-amino-benzoic 2-hydroxy-3-naphthoic acid2:5-dimethyl-4-benzoyl- Scarlet. acid.(3-carboxy)-phenylamino-l-aminobenzene. amide. amide.

2 do .do 2:5-dimethoxy-4-benzoyl- Red.

amino-l-aminobenzene.

3 4-methoxy-3-an1ino bonzoic 2-hydroxy-3-naphthoio acid2:5-dichloro'4-benzoyl- Ruby.

acid. (3-carboxy-6'-chloro)- amino-Laminobenzene.

phenylamide.

4 d0 rln 2-methyoxy-5-chloro-4- Do.

benzoylamino-l-aminobenzene.

5 do 2-hydroxy-3-naphthoic acid 2:5-dichloro-4-benzoyl- D0.

(3-carboxy-6-methoxy)- amino-1-aminobenzene. phenylamide.

6 4-ehloro-3-amino benzoic 2-hydroxy-3-naphthoic acid2:5-dimethyl-4-benzoyl- Orange acid (4-c(aitrboxy)-phenylamino-l-aminobcnzene.

arm e.

7 (lo rlo 2:5-dicl1loro-4-benzoyl- Do.

amino-l-aminobenzene.

8 5-a1nino-2z4-dichlor0- 2-hydroxy-3-naphthoic acid2:5-dichl0ro-4-benzoyl- Scarlet.

benzoic acid. (3-carboxy-zW-dichloro) amino-l-aminobenzene.

phenylamide.

9 2:4-dichloro-5-amino- 2-hydr'oxy-3-naphthoic acid2:5-dichloro-4-benzoyl- Orange.

benozic acid, (3-cgrboxy) -pheny1- amino-l-aminobenzene.

amr e.

No. I II III IV 4-ch1oro'3-amino-benzoic 2-hydroxy-3-naphthoic acid2:5-dichloro-4-benzoyl- Scarlet. acid. (3-carboxy-6-methoxy)-amino-l-aminobenzene.

phenylamide.

11 do 2-hydroxy-3-naphthoic acid do Do.

(2-nitr0-4-carboxy)- phenylamide.

12 3-an1inobenzoic acid 2-hydroxy-8-naphthoic acid do Do.

(3-carboxy)-pheny1- amide.

13 4-a1nino'3-nitro-benzoic 2hydroxy-3-naphthoic acid do Yellowacid.(3-carboxy)- phenylorange.

amide.

14 do 2-hydroxy-3-naphthoic acid do Orange.

(2-nitro-4-carboxy)- phcnylamide.

15 4-methoxy-3-amino-benzoic 2-hydr0xy-3-naphth0ic acid 2z5-dichloro-4benzoylami- Ruby.

acid. (3 -arboxy)-phenylano-l-aminobenzene.

IILl e. 16 4-methoxy3-amino-benz0i0 2-hydroxy-3-na-phthoic2:5-dichloro-4-(4-chloro)- Do. acid. acid (3-carboxy)-benzoyl-amino-l-aminophenylamide. benzene.

17 do 2-hydroxy-3-naphthoic 2:5-dichlor0-4-benzoyl- Do.

acid (3-carboxy-6- amino-l-aminobenzene. methyD-phenylamide.

18 4-ethoxy-3-amino-benzoic 2-hydroxy-3-naphthoic .do Do.

acid. acid (3-carboxy)- phenylarnide.

19 dn d0 2:5-dichloro-4-(4-chloro)- Do.

benzoylamino-l-aminobenzene.

20 4methoxy-3-amino-benzoic 2-hydroxy-3-naphthoic2:5-dichloro-4(4-chloro)- Redacid. acid6-brom0-(3-carbenzoylamino-l-aminoviolet.

boxy)-phenylamino. benzene.

21 4-chloro-3-amino-benzoic 2-hydroxy-3-naphthoic d0 Scarlet.

acid. acid (3-carbcxy)- phenylamide.

22 4br0mo-3-amino-benzoic 2-hydroxy-3-naphthoic2:5-dichloro-4-benzoylami- Red.

acid. acid-(3-carboxy)- no-l-aminobenzene.

phenylamide.

23 do do 2:5-dichloro-4-(4-chloro)- D0.

benzoylamino-l-aminobenzene.

24 4-(4-chloro)-phenoxy-3- do 2:5-dichloro-4-benzoylami- Scarlet.

amino-benzoic acid. no-l-aminobenzene.

25 fln dn 2:5-dichloro-4-(4-chlor0)- Do.

benzoylamino-l-aminobenzene.

dn d0 2zs-dimethoxyt-benzoyla- Do.

mino-Laminobenzene.

27 n dn 2:5-dichloro-4acetylamino- Do.

l-aminobenzene.

28 4 amino-3 m'trobenzoic 2-hydroxy-3-naphthoic2:5-dichl0ro-4-benz0ylanii- Yellowacid. acid (3-carboxy-6-no-l-aminobenzene. orange.

chloro)-phenylamide.

29 dn rln 2:5-dichloro-4-(4-chlcro)- Orange.

benzoylamino-l-l-aminobenzene.

30 do 2:5-dich10ro-4-(2:4-di- Do.

chloro)-benz0ylamino-1- aminobenzene.

31 do fin 2:5-dichloro-4-(2-ch1oro)- D0.

benzoylamino-l-aminobenzene.

32 4-methyl-3-amino-benzoic 2-hydroxy-3-naphthoic-2:5-dichl0ro-4benzoylami- Red.

acid. acid-3-carboxy)- no-l-aminobenzene.

phenylamide.

Example 2 are introduced into 500 parts of ortho-dichlorobenzene 0 5.30parts of the dicarboxylic acid chloride of the at 30 1 Whle f 12 PartSof f formula benzoylannno-l-alninobenzene In 200 parts of ortho-diand5.25 parts of the dicarboxylic acid chloride of the formulachlorobenzene are poured in, and the whole is heated at 140-l45 C. for16 hours. The precipitated crystalline pigment is filtered off at C.,washed with hot orthodichlorobenzene, benzene and methanol, and thendried in vacuo at 7080 C. A red powder is obtained which is verysparingly soluble in organic solvents and colors polyvinyl chloridefoils pure bluish red tints of very good fastness to migration andlight.

Example 3 65 parts of stabilized polyvinyl chloride, 35 parts of dioctylphthalate and 0.2 part of the pigment obtained as described in thesecond paragraph of Example 1 are mixed together, and then workedto-and-fro on a tworoller mill for 7 minutes at C. A scarlet foil isobtained which possesses a very good fastness to light and migration.

.7 8 What is claimed is: 1. An azo-dyestuff which corresponds to theformula N=N A I CONHC NHOO o OH I Y Z2 CONH III CONHC -NHCO o in which Zrepresents a member selected from the group 4. The dyestufi of theformula consisting of methyl, methoxy, chlorophenoxy, nitro Br groups,chlorine and bromine atoms, Z a member sel lected from the groupconsisting of hydrogen and bro- C mine, X and Y are members selectedfrom the group con- L sisting of hydrogen, chlorine and bromine atoms,and

methyl and alkoxy groups containing at most 2 carbon atoms, and in whichthe CONH group in ring A is CH3 at least 3 nuclear carbon atoms awayfrom the azo group, and at least 3 nuclear carbon atoms away from Z andI the benzene nuclei A, B and C may be further substituted C by chlorineatoms.

2. The dyestuff of the formula 5 1 ONHQNHC 0-0-01 5. The dyestuif of theformula 3. The dyestufi' of the formula 6. The dyestufi of the formular-C} r N- (31 Q N 0 3 3 N ONH- NHOO I OH 1 CONHO 01 -o ONH- 01 I I Noreferences cited.

1. AN AZO-DYESTUFF WHICH CORRESPONDS TO THE FORMULA